The prank was started by 4chan’s politically incorrect board, /pol/, in an effort to rile up feminists and make them (and men) look like idiots.

“This is a holiday celebrating misogyny, demanding appreciation and gifts for doing what a father should be doing anyway, especially when almost all cases of domestic abuse stem from the father,” an anonymous user on /pol/ wrote.

“Fathers all over the country are refusing to pay alimony or child support, which should not celebrated and rewarded, but should be shamed. ‘Father's Day’ should not be about celebrating the role of a father in the family, but about correcting it. It shouldn't be celebrated in its present form.”

Both of these hashtags are part of a six-month-long prank war 4chan launched against feminists.

The first prank to get traction was Operation Bikini Bridge in January, a scheme started by 4chan’s random imageboard /b/. The objective was to spam social media and get news organizations like CNN to report that the bikini bridge—what happens when a bikini bottom is stretched between the two hipbones—was a shocking new fashion phenomenon, the next wave of “thinspo” or pro-anorexia social media.

4chan followed this up with Operation Freebleeding, which tried to convince women that the use of sanitary pads was a male construction to keep them down.